Psone screen problem

[SNESGuy2]

i recently got a psone with screen and battery. I know the av in jack on the back uses a camcorder cable. The cable i used was from a leapster, but it has composite plugs on one end and a plug that is exactly like camcorder cable (The one with three black bands) however, when i plug it into the screen it fits very loosely in the jack and i don't get a picture or sound unless i move the cable up (which causes the metal part of the plug to go down inside the jack) Is the cable one i shouldn't be using, or is the av in jack screwed up?